Yield monitor systems are used to measure crop yields during harvesting. Yield characteristics, such as one or more of weight or moisture content, are used to assess the quality and quantity of a crop and accordingly determine its purchase price. In one example a yield equation that assesses the quality and quantity of a crop is based on four distinct variables and a fifth related variable. The four variables include volume, temperature, moisture, and test weight (density) of the harvested crop. The fifth related variable is the weight of the harvested crop, and with at least some yield monitors the weight is determined according to the volume and test weight. Additionally, crop moisture content directly affects the crop weight. Further, in some instances there are limitations on acceptable moisture content for specific crops. Accordingly, determining moisture content of a crop is typically conducted prior to selling or purchasing crop.
One example of a moisture sensor used with crop flows includes one or more capacitance plates configured to determine the capacitance of a crop as it passes each of the one or more plates. The measured capacitance signal is conditioned and converted into moisture content.